Tuesday, September 29, 2015

New Subject and More Exciting Work!

As a final recap, the new beam antenna is up and running and I am pleased with the results. A real highlight and icing on the cake was on September 27th, 2015 when I finally had an "on the air" contact with Bill N2CQR. Bill and I have fun talking about ham radio "stuff" on the SolderSmoke Podcast but have never had an on the air QSO. This was also a first for Bill as it was the first time he had a HTH (Homebrew to Homebrew) QSO. Bill was running his BITX 20 and I was using the ZIA. What a joy to have the HTH and even better with Bill. See the SolderSmoke Blog for an audio recording of the QSO.

Time to Move on to Radio Hardware

During the course of the SolderSmoke Podcasts Bill and I frequently encourage the art of homebrewing by starting with simple projects such as the Michigan Mighty Mite (M3) transmitter. This project is a functioning transmitter with only 7 parts (well I use 8 --a capacitor key click filter). BUT before actually putting this on the air you need to add a low pass filter which adds about another 5 parts. So with 12 parts you are on the air with a whopping 1/2 watt signal on 80 Meters. One podcast listener emailed us to say that he had built the M3 (M cubed) and now what a about a receiver. Thus the idea was born to come up with the companion receiver that could grow from a direct conversion type to something akin to the W1FB bare bones Superheterodyne. Then the idea has now further grown into developing a book with my able friend and co-author Ben, KK6FUT. Ultimately this project will morph into a functioning SSB transceiver.

We have had many emails both as a result of the podcasts and many of the articles I have written or co-written for QRP Quarterly that typically say I want to build my own rig but don't know where to start. The answer is very basic --start small! Many times the lure of a kit turns into disappointment first because of the cost and second the level of complexity.The M3 is a really good start as it satisfies the criteria of low cost and minimal level of complexity. Now moving ahead to build a companion receiver, this blog will focus on that aspect.

Moving ahead also involves a couple of other changes and we strongly suggest moving the M3 to 40 Meters and the frequency of choice is 7.030 MHz which is the internationally recognized QRP calling frequency. Several suppliers sell these crystals in the $3 to $5 range. [Halted Specialties, ESE and the GQRP Club to name a few.] The other changes involve moving the tank coil to 40 Meters. About 1/2 the turns used for 80 Meters will do it and the tap is 1/3 the number of turns from the bottom. You will also need less tuning capacitance to resonate on 40 Meters. By shifting the frequency to 40M has several benefits including: more activity, a smaller antenna and the possibility of DX running only 1/2 watt.

Thus the companion Simple-ceiver is designed for 40M. There is also another benefit for the choice of 40M as the receiver crystal filter will be on 12.096 MHz which only requires a 5 MHz Local Oscillator to put the rig on 40 Meters. Our intent is to offer at least four options for the local oscillator including a crystal switched VXO, a standard LC oscillator, the AD9850 DDS driven by an Arduino and the ultimate Si5351 PLL also driven by an Arduino. But lets not get too far ahead of ourselves.

The Art of Homebrewing!

The art of successful homebrewing does not start by heating up the soldering iron and cutting off a chunk of solder. That is the last step and the first is to recognize that homebrewing is first and foremost a disciplined process. Our next post will detail that process. But to put you in the homebrew mood here is an example of a homebrewed transceiver during the bread board stage.

Sunday, September 27, 2015

The Final Piece - Post Mortem!

My dream beam is up and operating and I surely can tell the difference! The front to side and front to back attenuation is very evident and I have netted quite a few contacts running 100 watts with my ZIA transceiver on 20 Meters. The signal reports are very good even with crappy band conditions so all and all I am a happy camper.

The cost of this installation --well I stopped counting after $2300. The mast with accessories and delivery was close to $800. The beam with shipping was $500 and the rotator with free shipping was $300. The coax and rotator cables were $250. The US Tower base plate with shipping was about $100. The Home Depot hardware was $100 and the contractor was $200. That is a lot to spend for a beam that ostensibly will be used during the down part of the solar cycle. But given where I am age wise this is probably not all a bad decision. For about another $1000 I probably could have had a 40 foot tower and a three element beam. But never look back.

Some lessons learned:

The information from the manufacturers is not very good or not even present. SpiderBeam does not have an instruction manual! Given that I am bottom rotating the mast I was told very few are sold for this purpose especially in a fixed location installation thus no manual. I did receive good factory support when I asked about drilling the mast for the bottom mast to rotator adapter and how to route the coax from the beam -- however, this should be standard information and not require emails to the factory.

Yaesu (I am using Model G450) has a standard calibration process for zeroing the rotator so when you are north the beam is actually pointing north. However there are several steps which are not clear and I had to call the factory -- and sort of got "Oh yeah we get calls about that all of the time." So I am not the only one.

I purchased a Mosley custom beam the Model MP-32-N which has the high power driven element from a TA-32 and the lower power reflector from the TA-32- Jr. The instructions are for the most part are OK except for three items. 1) There is an anti-corrosion compound that must be applied to all metal to metal mechanically connected parts. The only place this is mentioned is on the pictorial assembly drawing. The actual assembly instructions about fit Tab A into Slot B are silent on this matter. So if I had not spotted the note on the pictorial drawing my install would have lacked the compound. 2) Routing of the coax from the beam. I called the factory and inquired about a choke balun. I was told that is a really good idea and was given the dimensions. So why is not this just standard practice to say build a choke balun? Actually using the balun facilitates routing of the coax. 3) Where to place the boom to mast bracket? The parts are color coded and one of the final instructions says align the boom to mast bracket with the black index marks on the boom. Mine didn't have such marks and so I called the factory and was told it should be in the middle at the balance point (36 inches). The word balance point rang my bell! The driven element is heavier given the larger traps and size of tubing. So the balance point has to be closer to the driven element. I used a crude mechanism to create a balance structure ( a couple of stacked 1 X1 "'s ) and moved the boom along the balance beam until I found the balance point --which is 28" from the driven element. So why isn't that information in the assembly instructions?

This will be the last post on my antenna and future posts will concentrate on the Simple-ceiver.

Friday, September 25, 2015

We are there -- the Joy of Rotation

Two short videos to demonstrate the Joy of Rotation. We have some clean up to do and will test the Beam later this afternoon. In part 20 I will share lessons learned and things the manufacturers and suppliers could do better to enable a successful installation the first time.

Tuesday, September 22, 2015

The Beam Is On The Mast!

9/24/2015 ~ The contractor will be here on 9/25 to assist with the mast raising. Received some sage advice affirming that the final raising of the mast needs multiple pairs of hands to do it properly! Stay tuned. Pete N6QW

Yesterday and today I spent getting the beam mounted on the mast. That was a chore but it became obvious I could not raise the mast/beam combination singlehandedly. Thus I am attempting to hire local contractor to do the final erection. I just don't feel comfortable climbing on the roof. I have used this contractor before and am just waiting for a break in his schedule.

In the process of manhandling the beam onto the roof I moved the reflector out of alignment (same plane as the driven element). I need to reset the reflector so it is horizontal.

Sunday, September 20, 2015

Final Beam Alignment and Installations

In preparation for the final installation on the mast and then raising the beam I wanted to have one final go at torqueing all of the bolts and to upsize the connections from the SO-239 to the driven element. Initially I used about a #16 stranded wire and a voice in my head said make it bigger so that was changed out to #14 stranded. I used shrink tubing at all wire to connector interfaces and added the anti-corrosion compound at all the mechanical connection points.

I came up with what I thought to be an innovative idea for this last step. We have a six place metal picnic table with a large umbrella in the center of the table. It so happens that the umbrella mast is the same size as the mast used on the SpiderMast top section. Light Bulb moment. I installed the MP-32-N on the umbrella mast and using two wood blocks to clear the boom to mast bracket I was able to insure the beam was in a horizontal plane and provided access for bolt torqueing at waist level. My back thanks the light bulb moment.

Here is a short video of this final operation before moving the beam to the mast.

Thursday, September 17, 2015

Final Assembly of the Mosley MP-32-N

Additional photos added on 9/17/2015

Today I spent working on two activities. The first is the final assembly of the beam itself and the second to raise the mast to the final height so I could cut to length the guys that will be used. The SpiderBeam mast uses two sets of guys wires and thus we will have six lengths of wires that we must fit and cut. Below are photos of the beam as it is assembled into the final configuration. The instructions were silent about some aids that would make the final assembly of the beam an easier task than simply putting Tab A into slot B.

My approach was to build each of the two halves of the driven element and reflector and THEN assemble those on the boom. I used some wood blocks on my picnic table to keep things steady and level so that the two elements ultimately end up in the same horizontal plane when installed on the boom. The several photos with the coax connector is a mod from N6QW and somewhat put down by Mosley. In essence Mosley said unless you can keep the leads less than 2.5 inches don't do it. Well I am at 3 inches and so I am going for it. Mosley claimed the loses would be too high by using a coax connector. The cable I bought has super premium PL-259's installed (costly) and so I think I will be OK with the extra 1/2 inch lead length --we are not operating at Microwave frequencies here.

Pete N6QW

The next several photos show how I tested if the boom to mast bracket was perpendicular to the boom. I first made certain that the beam elements were in the same plane and then I installed a short section of mast that I had in the junk box. I then firmly affixed the boom bracket to the masts section and then moved the portion that attaches to the boom small increments so that a level placed on the mast section was "plumb" in two direction. Next I carefully tightened the U bolts which affix the adapter to the boom and we are there. Bob's your Uncle. We are really getting closer to B Day.

Pete N6QW

The second task was to "psych out" what was needed for the buying of the mast. The Radio Gods smiled down on me! It seems like I can use the wooden fence on three sides of my house as the guy anchor points for the mast. Luck Indeed! This test was just for the top most guys. I ran out of ti9me and will install the 2nd set tomorrow. Same anchor points.

Wednesday, September 16, 2015

Really Building the Beam!

Getting Close to B Day (Beam Day)

Test of Mast Assembly

Below are some photos of the elements that have been built. You will also see what I mentioned in an earlier post about the size difference in the traps used on the TA-32 Jr N versus those traps used on the TA-32.

The normal procedure is to install the coax is a direct wire connection from the coax to the driven element on the beam. My bent is to install a coax connector. Mosley is not too keen on that idea because of losses but did say if I decided to do that to keep the lead length to no more than 2.5 inches.

Today I fabricated an L bracket from a piece of one inch wide aluminum angle stock and designed it so the bracket is held in place by one of the sets of U bolts that affix the driven element to the boom. It looks like with this arrangement we may meet the 2.5 inch criteria.

Assembling the Beam ~ Mosley MP-32-N

(Information added on 9/16/2015)

Since it was raining out I took the opportunity to assemble the beam elements and would like to report the following.

I essentially assembled the two driven element sub-assemblies as well as the two sections of the reflector. In the final assembly of the reflector these two section fit inside a 6 foot long center tube that has two 1/4 inch holes closely spaced in the center of this section. Ultimately a U bolt clamps the reflector to the boom by passing through this section.

The two reflector subassemblies fit within this center tube and there is significant overlap (almost three feet on each end). In the final configuration the reflector subassembly ends have 1/4 inch holes align with the two closely spaced 1/4 inch holes and a U bolt which grasps the boom passes through a support block and through the aligned holes. While the tubing for the reflector is of a lesser diameter the center tube with significant overlap of the reflector sub-assemblies makes for a structurally solid assembly.

There is a good deal of clever engineering in how the beam is constructed and assembled. Yes I did put the anti-corrosion compound on the joints and that did make the telescoping much easier. There is a note that certain of the holes that are drilled were not de-burred at the factory and that is left to the customer. Because of the tight fit of the telescoping sections it is imperative that the holes are "clean".

The form, fit and function are superb. All holes aligned perfectly and all the hardware was present. There is slightly different hardware for the MP-32-N because the driven element is larger than the driven element for the TA-32-Jr-N thus the BOM is slightly different but well covered on the addendum page for the MP-32-N.

I have made an inquiry to Mosley about fabricating a small L bracket that would be attached to one of the set of holes used for holding the driven element to the boom. My intent would be to mount a bulkhead SO-239 Coax Connector on the L Bracket and then route the beam connections to this coax connector. Then the coax cable could be simply screwed on to the bulkhead connector and the whole assembly taped with coax seal. The factory install of the coax is to peel back 6 to 8 inches of the braid and put terminal lugs on the braid and center conductor. I would be concerned about water intrusion into the coax.

We are still about a week away from the final hoisting of the beam but we are certainly closer.

Pete N6QW

Back to the Beam Installation.

I spoke to a Mosley technical person on 9/14/2015 and my several question were answered. Seems like I was sent an old (older) instruction manual and most of my questions are answered in the new manual.

There are pre-drilled holes for all pieces including the Phone and CW settings.

Penatrox should be applied sparingly

A choke balun IS a good idea 5 Turns, six inches in diameter rolled up like a garden hose and the coax can be taped to the boom.

There is already a hole in the boom to mast bracket to pin that assembly to the mast BUT it is not recommended. The reason and the same applies to not pinning the elements to the boom based on any wind load greater than 80 MPH would transfer that energy to the tower or mast. By being somewhat free to move --the theory is it is easier to straighten out the element. beam, boom alignment versus fixing a tower or mast.

The driven element (because a reflector is used and not a director) is the front of the beam.

﻿

I took a short break from installing the new beam antenna principally because it was just too hot in Southern California where we had several days this past week with temperatures hitting 100 Degrees F. The forecast indicates a cooling down to the high 70's so back to the beam installation.

The beam I chose is manufactured by Mosley Electronics located in Union, Missouri. Yes guys something actually made in America but the Aluminum probably came from offshore --but that is OK. The specific model I chose is a non-standard catalog item called the MP-32-N.

Basically the antenna is a TA-32 Jr. N by design but is a hybrid in that the driven element is from a TA-32 (legal limit) beam and the reflector is from the TA-32 Jr. In its original configuration the TA-32 Jr. is good for maybe around 1 KW PEP. But with the driven element from the TA-32, the custom hybrid MP-32-N can do the legal limit. Thus I can use my 3CPX1500 A7 homebrew linear amp with this antenna. You can see the difference in the size of the traps with the Jr traps being like 1" in diameter and the legal limit being like 2" in diameter. (These may not be the actual sizes but are stated only to give a relative feel of the size differences.)

Being a two element beam, its forward gain is only about 3 DB on 20M but does have a decent FB ratio of 20 DB. With a less than six foot boom and weighing around 20 pounds it is the best compromise for the mast being used, the footprint on the roof and the neighborhood aesthetics. Having the ability to rotate the beam is another desirable feature even though it is a puny 3 DB gain.

Here Comes the Ranting!

The beam arrived over a week ago; but given our crappy weather it just sat in the box until yesterday when I got around to opening the box. The MP-32-N came very well packed and it survived the trip to SoCal in fine fashion. The first thing I did was to retrieve the Instruction/Assembly Manual and the scant 4 pages quickly told me that this was going to be somewhat problematic. I did not look at the hardware in detail but wanted to start with the manual to see if it was clear what needed to be done. Well having lived in Missouri for about 11 years (not too far from Union) I know that there is a lot of local resident tribal knowledge about how mechanical things get assembled. But not everyone has those mechanical assembly gene's flowing through their bodies --including me. So here is what I see from just reading the manual.

For ease of assembly parts are color coded. Red is used for the driven element and those with a yellow mark are for the reflector. That is good -- but in my case I will use the parts with a blue marking since the MP-32-N has a driven element from the TA-32. In any event color is good.

The actual assembly instructions (Tab A into Slot B) are on a single sheet of the four pages and there is an exploded assembly view which links the parts in the assembly pictorial with a Bill Of Material parts list. There is a special insert for assembly of the MP-32-N driven element as the baseline instructions are for the TA-32 Jr. N and the driven element of course is from the TA-32. That part is OK

The first hiccup involves the single sheet of the assembly instructions which tells you Tab A into slot B, and the pictorial of the assembly sequence. The single page instruction is absolutely silent about the use of the anti-corrosion compound (Penatrox). A note in the lower right hand corner of the pictorial drawing says you must use this compound or the pieces will not telescope and evidently over time corrosion will impact the electrical conductivity of the beam elements. The note is easy to miss.

Once again I have not actually touched the beam hardware but want to use the instructions as a first step to assure myself that it is absolutely clear what needs to be done. On the page which contains the BOM there is a dimensional sketch which shows the final length of the beam elements for what is called condition II -- these condition relate to whether you set the beam to favor the CW portions of the band or the phone portions. Obviously favoring the CW portion would make the elements longer and the drawing shows the dimensions for SSB and notes that about 10.5 inches would need to be added for the CW centering. I gather there may be predrilled holes that let you do this; as there is a notation that there are sets of holes on the driven element traps to enable this. While there is mention about adjustment on the reflector for the CW band, again I am not certain there are predrilled holes.

In the assembly of the driven element there is a caution on the drawing about attaching the terminal lugs to the driven element and then soldering the coax as the material that holds the driven element ends. This insulator material is obviously plastic and you will melt the insulator if you try to solder the coax with the terminal installed on the insulator. That is understood. But if you install the terminal lugs on the coax, can the installation of the coax be done later or is the assembly sequence such that you must install the coax mid process and thus you have this lump of wire hanging out all over the place. The instructions almost lead you to believe that.

Speaking of the coax there are no instructions how to route the coax from the connection point away from the beam like looping the coax over the end of the beam and then taping the coax to the boom Should some sort of coax seal be place over the mechanical connection to the driven element? If there is effort to use Penatrox on the aluminum connections, what about these two connections to the driven element? The instructions emphatically state 52 Ohm coax must be used but are silent about any sort of 1:1 choke balun. Needed or not?

The instructions are silent about "what points what" on the beam direction. In other words if it is a driven element and a reflector combination, is the "front" of the beam the driven element and the back the reflector. Were it a driven element and a director then it follows is the back of the beam the driven element. But nothing is said.

Having had two beams previously (both Hy-Gain, one a 2 element and the other a Tri-Band) there is the ever present problem that because "U Bolts" are used to hold the elements to the boom and the boom to the mast adapter that there will be a subsequent alignment problem within the same plane or that the beam remains in a horizontal plane. A further concern is that the beam rotates around the mast to a position different than originally established. The point here is that there should be either some specification that establishes the proper amount of tightening (torque) to prevent any of these situations or that a mechanical solution is available. I intend to drill at least one hole in the boom to mast base plate so that a pin can be installed to firmly affix the boom to mast bracket to my mast. For the two elements I will assure sufficient torque on the U bolts to firmly hold the elements from moving on the boom while not permanently compressing (depressing) the metal tubes. At the very least Mosley could mentions these issues so that the builder is aware of the possibilities of these events occurring. Yes Mosley -- this might mean 5 pages in your instruction/assembly manual.

Too bad there is not some intermediate setting between CW and phone. Sure would appreciate hearing from anyone who has a TA-32 Jr. N and their experience with this product. n6qwham@gmail.com. 73. Pete N6QW﻿

Wednesday, September 9, 2015

Another Short Diversion from the New Antenna Build

For the last week or so the temperatures in southern California have been inching toward 100 Degrees F. It is just too hot to work outdoors and the next step involves assembling the 2 element Tri-Band beam which of course would be done outdoors. So I have taken a short break from the antenna installation to work on a radio project in hopes that the temperatures get back into the 80's.

So now the temperatures are down But believe it or not is raining --we direly need the rain. But there is so much junk in my garage that the beam can only be assembled out doors so back to the Simpleceiver while I wait for the weather to clear

In the back of my mind I have been thinking about building a simple super-heterodyne receiver that could be easily replicated, has a low part count yet some nice features like a 3 pole crystal filter. In searching my junk box I found some 12.096 MHz crystals which if used with a 5.0 MHz LO would put you on 40 Meters. Another design goal was small (like to take it portable) so some of the circuitry would be surface mount. I have tried several LO's with the receiver including an LC oscillator, a varactor tuned NE602 configured as an oscillator followed by a MMIC RF amp stage and finally the Si5351 using only the Clock 0 output. Below is a Block Diagram of what I call the "Simpleceiver".

The upper photo shows the Simpleceiver with the NE602 Oscillator and the lower one with the VFO. A future evaluation will be to switch between the LC VFO and the Si5351.

Unfortunately some well respected members of the homebrew Illuminati community have panned the Si5351 claiming that such devices when used in home brew radios are totally unsuitable arising from the Si5351 phase noise signature. My experience has been entirely different.

I added the second LO where you can switch between the LC VFO and the Si5351. I sure couldn't tell any difference.There will be a new direction for this Simpleceiver which you will hear more about in the future. I am impressed with how well it works with such few parts.

Monday, September 7, 2015

The Mast is in the Air!

Houston we have an Erection (of the mast).

Below is a photo essay of the first time in air of the Spiderbeam mast assembly. This is not the full height -- when I was trying to pull out the very top section it slipped out of my hand right into the nested pipe. So the final height will be about 6 feet taller than what is seen in the photos.

Right now the mast is being supported with out guy wires using only the rotor base and my homebrew house bracket. I strongly recommend the house bracket when making the SpiderBeam Mast a permanent installation.

It will only be up for a short while sans the guy wires but this will enable me to accurately cut and deploy the guy wires (actually magic rope --for what it cost me, it has to be magic). This mast deployment also enabled me to get a feel of how high the beam will reach above the house structure and the aesthetics of how it will look. The photos show the SpiderBeam Mast next to my fiberglass mast used to hold up my current wire antenna. This is getting exciting!

Thursday, September 3, 2015

More Preparations for the Installation

Houston: We have Rotation!

Hopefully I won't be boring the readers much longer with this, what I now believe. was somewhat of an insane project. Much is happening in the background in preparation for the final erection of the beam on the mast and the hoisting of the mast into the air. There are just so many details that must be in place and anyone who tells you their accomplishment of a similar project was done in one day must be awfully lucky or that the install will not last the winter!

Here are some of the tasks which have been going on in preparation for the final installation.

The key issue is that the rotator must be capable of bottom rotating the mast and to do this properly requires having the rotator in a level position. A bit of rework was required to have that occur and luckily my idea of having the threaded portion of the anchor bolts be sufficiently long so as to accommodate a nut and washer underneath the L bracket assembly plus a nut on the top portion of the L bracket to secure the US Tower RP-3 to the anchor bolts. The bottom nut plus washer acts as a jack screw and a level placed on the three corners of the RP-3 must indicate being level at those three points. It took a bit of juggling amongst the three location but the RP-3 is now flat level!

The rotator itself must be calibrated so that when the indicator points north the beam is pointing north ( 0 Degrees) and when you perform a full rotation the beam is pointing north (360 Degrees). The instructions are a little confusing but a call to Yaesu confirmed I was not crazy and so that part is done. Yaesu's instructions were adamant -- do this process on the bench as it took a while and the last thing you want to do is climb a tower to get this done. Luckily with a bottom mount not so much of a problem.

The SpiderBeam Mast is intended to be rotated from the bottom and to keep the mast vertical two sets of guying rings and wires are used to make that happen. I just did not feel comfortable that this would be easily done! So my plan was to fabricate a sleeved bearing assembly that would capture the mast at about the 8 foot level to provide an additional vertical guide to the mast during rotation and to take up any side loading from wind acting on the beam/mast. The final configuration consists of a house bracket mounted to the eaves of my home and a two piece saddle assembly formed by a piece of 2X4 which was hand cut to be slightly larger in diameter than the mast and covers about half of the diameter of the mast section. The second piece of the bearing is made from conduit clamp material that is then screwed into the 2X4. The conduit clamp is wrapped with vinyl tape so it doe not abrade the metal mast. The 2X4 portion of the saddle is painted with epoxy paint. Luckily a piece of 2.5" PVC pipe union is about the outside diameter of the mast section at the bracket location. So this union served as a template of how much of the 2x4 needed to be carved out to capture the mast and this is shown below.

The Mosley 2 element beam arrived yesterday and weighs about 18 pounds. It has not been assembled as yet but I can see already some issue with raising the beam and the mast as it get higher in the air and my ability to push up the mast to the 30 foot level as a one man job. I will also have to address the beam to mast assembly so that the beam does freewheel on the mast and will require some sort of pin anchor.

Having completed the house bracket and assuring my self that the mast section when placed in the bracket would be in a true vertical position I temporarily installed the mast in the rotator and after having calibrated the G450, the temptation to try several cycle of rotation was just too great! Houston: We have Rotation! ﻿